Should we phone ET?

Sun 04 Jul 2010 10:37 PM

Stephen Hawking has been a great science popularizer. I first encountered his work when I was in junior high school. Before that, when people had asked what I wanted to be when I grew up, my standard answer had been cartoonist. After Hawking, my standard answer was astrophysicist. I went on to be a physics major as an undergraduate, which combined with my interest in philosophy to become a specialty in philosophy of science.

I am late to the blogging about this, but Hawking recently headlined a documentary series which, among other things, discussed the prospects of extraterrestrial life. The London Times story is typical; other news sites offer distinct but similar coverage.

There is likely to be alien life, Hawking reasons, because the universe is big. Crudely, the idea is that one should expect that any outcome which could does occur somewhere in a place that big. Extraterrestrial life is such an outcome, so we should expect it. This is pretty standard. It's the same as the reasoning in the Drake Equation, although Drake ornamented the argument with numerical probabilities so as to give it the illusion of rigor.

Yet the headlines were not that Hawking believes in aliens. Rather, it's that Hawking recommends against reaching out to alien civilizations. Aliens, he suggests, are likely to be a dangerous. The Times quotes him:

We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonise whatever planets they can reach.

Perhaps aliens would be jerks like us.

The prediction that they would be is certainly not a scientific one, and it is not within the purview of physics. So he's really out of his depth in speculating as to whether advances species are more likely to be saints or sinners.

Yet physics does have something to say about is the feasibility of traveling from world to world and pirating planets the way Somalians pirate a freighter. Physics is pretty down on the possibility. Hawking invokes artificial wormholes or whatever, but we're really in the science fiction turf of technobabble.

Kurt Vonnegut, in a little story called 'The Big Space Fuck', says this:

One of the most depressing things about the space program... was that it had demonstrated that fecundity was one hell of a long way off, if anywhere. Dumb people... and even fairly smart people... had been encouraged to believe that there was hospitality out there, and that Earth was just a piece of shit to use as a launching platform. Now Earth really was a piece of shit, and it was beginning to dawn on even dumb people that it might be the only inhabitable planet human beings would ever find.

The thing that Vonnegut has people realizing is the gist of what physics actually tells us. Hawking is saying what people had been encouraged to believe, only striking 'hospitality' and writing in 'malevolence'. Science fiction authors may introduce chronosynclastic infundibulae, but travel between here and any point where there might be extraterrestrial life is going to be too slow and too costly to make sense for even the most nomadic of space jerks.

I concede that my reaction is based on the marketing for Hawking's TV specials. There is, no doubt, some good science in them. Yet I find the whole thing a bit disappointing.


from: niku

Fri 03 Sep 2010 09:16 PM

"but travel between here and any point where there might be extraterrestrial life is going to be too slow and too costly" -- For humans, as far as our current understanding goes. Have you any reason to suspect that this is the "final" scheme of things?

Btw, I think humans should reach out to ET, for the same reason we must "progress". It may result in good or bad, but it would be terrible if we don't try it.

Also, the website is very good.

And, I had to enter this comment four times. Whether 'name' is filled or not must be checked _before_ submission. And (i) I got back to the page with the browser's Back button, (ii) the submission failed with "incorrect captcha".